Quote:This update is extremely important for anyone making use of the Shape Model capabilities in Occult. It is particularly important for all regional coordinators & processers of observation reports.


********
4.2023.4.25
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*  A major revision to the handling of Shape Models. Recently
    the models in the ISAM data base were renumbered in a
    way that distinguished between models present in the
    DAMIT system, and those that are only in the ISAM
    system. Advantage has been taken of this to remove the
    presence of duplicate models in the shape model solutions,
    by only using ISAM models that are unique to the ISAM
    system. [Such models have a model number of greater
    than 100].
   
    The consequences of this change have been:
    i. a reduction of around 6000 in the number of shape
    models retained in Occult
    ii. 43 ISAM models with model numbers greater than 100
    iii. A revision of the Asteroid~Observations file to
    remove all ISAM shape model solutions where the ISAM
    model is in DAMIT, and to renumber the remaining ISAM model
    numbers to their new number in ISAM.
    iv. Listing of Observed Diameters, and Shape Model
    Fits [accessed from the Asteroid Observations tab]
    no longer have fit results to an ISAM model where
    that model is also present in DAMIT. That is, all
    fit results relate to different models.
   
    =====================================================
              ****** VERY IMPORTANT ******
    =====================================================
    This update involves a change to the Occult program
    the Asteroid~Observations file, and the collection of
    ShapeModel files. The inter-relationship between the
    Asteroid~Observations file and the ShapeModel files
    creates a complication in updating. To avoid any
    possible problems, please follow the next steps closely.
   
    1. Start with Occult not running. If you have multiple
    instances of Occult running, close them all. 

    2. With Occult not running, locate the folder
    (subdirectory) called ShapeModels in the Occult 4
    directory. Rename that folder to something else - for
    example 'ShapeModels_toDelete'. [The update will
    create a new ShapeModels folder, which will only
    have about 6000 files - compared to about 12000 in
    the folder to be deleted]

    ====================================================
      *** IMPORTANT**** The next three downloads can be
      done in any order. But you MUST NOT USE any OCCULT
      functions until all three downloads have been
      completed. In particular, do not open the Asteroid
      Observations Editor until these three downloads
      have been completed
    ====================================================

    3. Now run Occult. From the main menu, do the usual
    update to Occult

    4. After that update has finished, go straight to
    the Download page, and Download #24 Shape models.

    5. Finally, download #3 Asteroid observations.

    Once you have done these three downloads, Occult
    will be fully functional. You can also delete the
    folder you renamed in step 2.

Dave Herald
Murrumbateman
Australia

Quote:A minor but important fix

The last version of Occult had a major change in the handling of ISAM shape models.

Unfortunately there was an oversight. The code has long included a check for whether new ISAM models might be available. After the revision in 4.2023.4.25, that check returned a wrong result. Furthermore, if you clicked the option to update the ISAM models, you would have downloaded all the shape models that had been deleted as part of that revision.

This version removes that check. So you will not see any invitation to download ISAM models.


Dave Herald
Murrumbateman
Australia